Process of preparing textile materials for bleaching.



TED sTnrnsPATENT (iF-Fiori.

y.mains Locxnnnriaaninn, vor PENICUIK, scornato);

11e Drawing.

T all whom 'it may concern Be it known that l, JAMES LOCKHART JAsmNE, a subject ofthe. Kingof Great Britain and Ireland, and-.al `resident of Peni cuik, in' the county ofh/LidLothian, AScotland, have invented a certain 'new yand use- -ful Process of Preparing Textile Materials for Bleaching, of which the following is the specification.

The invention 'consists inv substituting `a single process for the alternate alkaline (bowking) and acid (souring) treatments, as used inthe preparation of vegetable textile fibers for bleaching. I have discovered that the non-cellulose or incrusting constituents', which these chemical treatments, remove, can be resolved and rendered soluble by the use of asolutionA of a bisulte of a base (such as magnesium or sodium) which yields a soluble sulite. When using this bisulte solution, the liberated TSO, must be fully and completely removed so as to prevent the undue preponderance of acid in the solution, otherwise tendering of the fibers would occur due' to the formation of hydrocellulose. Further if the.' freedA SO2 be retained, reversals in the chemical action may occurwith the precipitation of organic substances of powerful reducing properties.

The digestion is carried out in'a closed vessel with acid proof liningunder prese sure, and heated preferablyA by -means .oli

coils or a jacket, or it may be heatedby the application of direct steam, and the tem' perature and percentage strength of the -solution are varied tofsut'- the material being treated, or the degree to which it is'de sired Ato'be bleached, butin all cases itis essential or`reasonsigiven above tol provide a` free outlet for the removal of the gaseous emanations, and this at the same time in` sures the Vuniform penetration ofthe liquor.

vResolution conducted under the above conditions effectively removes thev lignified incrustations as .well as the pectcse and gummyv ingredients, and astliere is no tend encyftoward mercerization, the structural formation of the fibers or filamentsare not i to the extent 'necessary much altered, and their' strength ,is not un-y duly impaired. So mild is thevaction and yet-so complete is the resolution'tha-t the.

. Specification of Letters Patent.

. l rnocnssor Pnnranino TEXTILE MATERIALS For. :Bilanci-amc. A,

Patented June 15, 191,5. sensation med February a, 1915. .serial no. 5,922.

bisulite liquor, (i. e. the proportion of, Vbasek and available or free SO2) is toa certain ex:

tent dependent upon the period of time and 4 the temperature of cooking-that is to say y' v.the s't'rongerthe liquor Athe shorter thetime at a given temperature, and vice ver'safthe"` eeet beingurther modiedjbyvariationin' l temperature. lThe component percentages suit the nature of the fiber being treated ac!y cording to its chemical charact'eristiesv f (pectic or lignin) and its physical condition" lanents or thiol; woven l of base and availableS()2 are also varied to of the SO2 gas vwhich is liberatedin the heatin or digestion. vided I y forming hydrocellulose, and as this product is -of a viriable nature, the strength 4of vthe liber or fabric is destroyed, or the presence of the excess acid may cause areversal' in the action, resulting in the deposition 'of an aldehyde which renders the iberdiiiicult to' lf this is not p'rovv r, the free acid will ail'ect theiiber,

bleach. The lignified incrustations ofthe.l

fibers are readily dissolved by the aetionfof the SO2, which ongbeing usednp inthis.

way, or liberated as gas, freesltlie basel' vwhich then attacks the pectic and guminy substances, resolving them, and thusfthe'.

joint result is the removal of the materials der the specified conditions is drastic, coupled with the fact that they throughoutthe process coact, the incrusting in edient'sare lwhich prevent bleaching. As neither the acid nor alkaline action of the bisulfite unremoved without risk of the ce lulose being l injured, and further, as there is no tendency toward mercerization, the structural-formation of thelibers or filaments, is not. materially 'altered, consequently their. weaving4 r propertiesor tensile strength is notunduly impaired. I The incrusting, ingredients combined ory associated with all the'bast or equivalent' I'bers are of lignin and pectic nature with y admixtures of gums and waxes, and A.to get full bleaching with the use of a `minimum percentage of theI hypochlorite or.l other,v bleaching agent, these must be more-'or less completely removed. Therefore S02 must be provided ,in `sufficient quantity `to sul-L fonate or dissolve the li in, but as itsexfposure, to the action of t isfacidis to; a ,cerf

Lie.

made from a magnesium base, One gallo for 1% lbs. of cloth. heating.;` is comvI nenced, and the full temperature off280 r four to -five hours.

cooking process afree dependent already 'given a strong acid temperature must not be applied), vess 4must proceed.' slowly with the pectic removal action of.4 the alkaline base.v substance is pronouncedly li 'th'jute, a liquor wit 16,. centa .'provi ed than or hemp',

. p onderate.

and hemp. and like pectic ingredients' of-li need be .applied for say 'n characteristics,

' 'i Anaeidgsuiate wiiibe quae suitable pro- 20.vided 'it contains, as .tissue is concerned, an excess .able SO -sdiinsur that all the' which is separated wi. at once be 'disse ved,

ing bythe exhaust.

e'taken that all the mpletely immersed, as o r burning will result.

f-sHavingmade .clear howthe-bisulte so1u' tion acts, 'I -now plied tofjute and hem The examples of the after 'ven were done in a. small nallyby gas.v Jute as raw sian cloth, freed from the oils with -i's placed inthe digester, solution giving the following analysis v of this liquor is used ;Theylid'being bolted down,

Fgdayreached in .Throughout all the i escape: to: atmosphere is of a sinall outlet pipe. During f stages Aofthe heating this is ke quickl remove jthe gasiiied` f aperture l must always be l revient-.the

.onltleremoval of thef'other incrustaiit's.- (and for the reasons or .too high a the procand concurrently which requires the the fibrous 'lied as is the a larger per-- Lof. free or available SO2 must be yflax here the pecticsubstances pre- So that when dealing 'with flax substances in which the preponderte overthose it is not necessary tov provide in the liquor when a sodium base used the full bisuliite proportions of S far as the vegeta of free or availrelief of' steamand the. ,Andi-ble or hee""'"" besides attainingthe has already been the removal of and liberates air, uniform liquor penetration. ibers are otherwise giveldet'ails of methods vvap digestione as. here-'- experimenta boiler lead lined and heated exterber, or in the'form of Heswhich'it has been impregnated to facilitate-spinning, and covered by a Combined; 1.4%'

v t0 development of false pijessu re o6 vm excess glthat equivalent t'ijrftli'e temperathe pressure will a ways be in accordance with the saturated steam equivalent of the temperature.' gases, concentration of the, liquor takes place, and water must `to time to keep the cloth covered.- Iiind that by maintainingv twenty thoroughly removed thata be easily obtained by the use of a relatively small'p'ereentage of a hypochlorite bleaching liquor. The

but this salt must be provides the carrier able SO2.

. Woven hemp,

ble

bisulite solution 'made from a'vmagnesim base -and .containing the following percentages-of SO2 j Total A f Combinedf-` 3` r i- 1.5 vyields a material which a. full white color..` larger pectic constituents, uses 'up moreo `thelbase,- and SO2 than in the case of ]ute, :cases the acid and matically regulate themselves to gradeY of material being treated. gree of chemicall action .largely controlled bythe the fibers have and thus it is verydesirable to con .-digestioir with the ple and open `a manner` as .stage ofresolution is but in both.

suit

extent to whi liquors, this does'f'not get below .25% no burning will occur. v 7

What .I claimfiszf-Q 1; A process of 'terials for and provided moving substantially I .SP3

.i'erfriove-l the incrusting suliiciently long.

t "e constituents, but not to red torials to the condition of pulp,y 1-proceda ofpre'parihg As'steam escapesl with' the -i' uce said textile Ina-- will?. miler."

ture and owing to,` asacciiiiiulation. Thus this temperature 'for hours .the incrusting matters are so white color can' residual liquor inthe digester contains a fairly large percentage of M gSQ-3,

present vin excess as 1t'v or the free or availtreated under simlar con i .i .l ditions asto time and temperaturewith a is easily bleached. This substance, havin f thereis a greater escapeoff` alkaline tendencies autoif the; y d'l `.he de 100 require is Ave been mechanically separated,

uctfthel r fibrous material in as sini-L possible. Thej -f determined by a of the total SO2 contained in the resolving .loir

preparing textile-'mableaching in a single operatio'm. which comprises treating said textile ma-` is water-soluble, the boilingvr point .ofy f which the fibers of or the textile .materials provided bythe use Areducadl. toa pulp,'said treatment being gef# the initial tfull opeiito 0 but thereafter,.a'sth e rate'of gasqliberationisslower, .th'e outlet maybe partially f'folose'fd; but.l li

.large enough all the liberated treatment.'being-.continued suiciently long toj `i point of Water, but "period of time less than that at which the ture, above the boiling point of Water? described. :Wold the formatlon of materml amounts of n testimony whereof hydrocellulose, and eontlnuing' 55nd trezw l `ment for about L Wlneh comprrses treatmg the same solutron of magnesium lnsulte, under presn sure, at a temperature above the borlmr;

below that and for :1

art-lon r structural formation of the textile materiel would be destroyed, or the textile meterle reduced to. a pulp or the fibers .mate h weakened, and removing substantially ell the liberated sulfur doxid during the ing step, whereby at first the acid salts in the liquor not upon the lgnn7 in said textre material and thereafter the bese in the. liep vor nets upon the pectc principles textile nmteral, but the physical structure of the material is not injured.

In the process of treating ruw en e materiels, to prepare the same for oleac''r ing, the step of subjectugthe seme to t" `ss equivalent te Said veter during ien; to rf l laced by Steen: eseepng nu@ action of a Solution of magnesium lsule of such a strength and at such ay name to 20 hours, While substantially continuously allowing the escape of sulfur dioxid, sullciently to avoid the development of a pressure nm terall f exceeding the steanr pressure equivalent to the temperature employed, and discontinuing said treatment be- Witnesses .LLMIES l enr: 

